Electric burglar-alarm.



Patented Sept. 14, 1909.

M. TRAUTMANN. lELI'GTEIG BUBGLR ALARM. lAPPLIOATION FILED 11011.21, 190s.

UNITED STATES rATnNT carica,

Max TRAUTMANN, or DRESDEN, GERMANY, AssIeNoa To Baarn-A Taeurnann, or DRESDEN, GERMANY.

ELECTRIC BURGQAR-ALARM.

Specification of Letters Patent.

Patented Sept. i4, 1909..

To aZZ whom it may concern:

Be it known that I, MAX TRAUTMANN, a subject of the German Emperor, residing at Dresden, in Germany, have invented certain new and useful Improvements in Electric Burglar-Alarms, of which the following is a specification.

This invention relates to electric burglar alarms of the type wherein a curtain or other swinging device suspended in front of the entrance or object to be guarded is so connected with operative and in-operative circuits that an alarm circuit is closed when said swinging object is disturbed.

A construction embodying the invention is illustrated in the annexed drawing in which- Figure l shows an elevation of the swinging object and a diagram of the circuits and Fig. 2 a longitudinal section of part of the ap aratus.

double walled curtain Z) is so attached to a roller a provided with a winding device that at the front and rear thereof a portion of the curtain hangs down freely providing a space b1 between the two curtain parts b2 3. Each of the latter has on the inside a plurality of contact bars c and UZ extending throughout the entire width of the curtain, the bars c being joined together by an electric circuit e and the bars Z by a second electric circuit f. Between the said curtain parts a plurality of electrically conductive chains g are fastened to the roller a and joined together by a circuit 12,. The circuit wires e f and ZL lead through terminals on the roller a to remotely situated known drop switches; for example wire e passes to a relay Z connected by a wire z' to a battery lc. TWire it passes to a switch j, the relay fm, of

"10 which is connected to a separate source of current a. Wire f leads to a relay o and through wires e to a battery la. An electric bell t connected by a wire a to the battery lc is connected by wires o and 1 to the armature i5 Z1 of relay Z and to an adjustable contact g respectively in the path of the switch The circuit s contains a normally open switch s1 and is c losed by pressure of a button w, which causes the switch y' to drop by '9 the relay m attracting its armature m1.

" The action of the apparatus is as follows The normally raised` curtain is lowered when the entrance is to be protected. By pressing the button lwthe switch j is dropped on to contact y connected by wire w to 'battery Ic, and closes a normally open circuit c it. A current then flows from chains g in contact with the contact bar c of one curtain part, through wire z, to switch j, Wlre a, battery c, wire z', relay Z, wire 'e and contact bar c. The relay Z attracts its armature Z1 and breaks the bell-circuit. If subsequently the circuit of the relay Z is broken, by disturbance of the curtain or by cutting the wires, the bell-circuit is closed and the bell rung. The chains g are attached to one side of the vertical plane of the longitudinal axis of the roller a, so that when the curtain is in its normal lowered position, as shown in Fig. 2, said chains will be in contact with the bars or elements c and out of contact with the bars or elements a?. When the curtain is rolled up, it will be understood that the bell circuit is broken so that no alarm will be sounded. Movement of the curtain also closes a closed circuit' by bringing the contact bars a? against the chains g, so that current flows through wire It, switch j, contact y, wire w, battery Zcwire e, relay o, wire f, contact bars Z and chains g, thus causing the armature o1 of relay o to be attracted and switch p to drop and make contact at g, to ring the bell t. rIhe alarm is therefore actuated by removing one part of the curtain from the chains and also by moving the other part against the chains; also by cutting or damaging the wires leading to it.

Vhat I claim as my invention and desire to secure by Letters Patent of the United States is l. An electric burglar alarm comprising in combination a movable swinging member having two depending portions, conductively connected iexible members suspended between said depending portions, two series of contact elements carrled by said swinging member one series being normally in contact with the flexible members and the other series out of contact therewith, a normally -open circuit, electrical connections between one of the series of contact elements and said normally open circuit, a closed circuit and electrical connections between the other series of contact elements and said closed circuit.

2. An 'electric burglar alarm comprising in combination a double curtain, a winding roller from which said curtain is suspended in two depending portions, conductively connected chains suspended from said winding llO . o en circuit, electrical connections between roller between said clepening portions, two l tween the series of Contact hars out of con- 10 series of contact bars on the .interior suitact with the chains and said closed circuit.- faces of the curtain one series bemg normally In 'witness whereof l have signed this in contact with the chelns and the other sespecification in the presence of two witnesses. ries out of contact therewith, a normally MAX TRAUTMANN;

t e series of contact bars in contact with the Witnesses: chains and said normally open circuit, a MORITZ SPREER, closed c lrcult and electrlcal connections be- RUDOLPH Fucine. 

